Conventional methods for modifying die bodies for extrusion of honeycomb bodies include plunge electrical discharge machining of the die body with a tool electrode having a matrix of web portions corresponding to an intersecting array of discharge slots extending into the die body. Such conventional methods are known to provide a conventional honeycomb extrusion die apparatus configured to produce a honeycomb body with cell walls that increase in width with increasing proximity to the outer periphery of the honeycomb body.